According to international treaties, phytosanitary measures against introduction and spread of invasive plant pests must be justified by a science-based pest risk analysis (PRA). Part of the PRA consists of an assessment of potential economic consequences. This paper evaluates the main available techniques for quantitative economic impact assessment: partial budgeting, partial equilibrium analysis, input output analysis, and computable general equilibrium analysis. These techniques differ in width of scope with respect to market mechanisms (relationships between supply, demand, and prices), and linkages between agriculture and other sectors of the economy. As a consequence, techniques differ in their ability to assess direct and indirect (e.g. economy-wide) effects of pest introduction. We provide an overview of traits of the available methods to support the selection of the most appropriate technique for conducting a PRA. Techniques with a wider scope require more elaborate data, and greater effort to conduct the analysis. Uncertainties are compounded as methods with greater scope are used. We propose that partial budgeting should be conducted in any risk assessment, while more sophisticated techniques should be employed if the expected gains in insight outweigh the costs and compounded uncertainties.

In late 2009, a European Food Safety Authority (EFSA)‐funded project (Prima phacie) began work to review and test methodologies for conducting pest risk assessment by means of case studies on three phytoplasmas (Candidatus Phytoplasma mali, Ca. P. prunorum, Ca. P. pyri); two bacteria (Acidovorax avenae subsp. citrulli, Xanthomonas citri [=X. axonopodis] pv. citri); two fungi (Guignardia citricarpa, Mycosphaerella dearnessii); two nematodes (Meloidogyne chitwoodi, M. fallax); and an insect (Anoplophora glabripennis). Multiple risk assessment schemes and methods will be applied to each of the case study pests, allowing for a comparative assessment of methods. Methods to assess the effectiveness of possible risk management options for each pest will also be evaluated. The project will further develop the scientific basis for pest risk assessment within the European Community and identify methodologies most suitable for conducting risk assessments and for evaluating the effectiveness of possible risk management options by the EFSA Panel on Plant Health in order to support European decision making. The project lasts 29 months, and is being conducted by an international consortium of 11 partners consisting of phytosanitary organizations, research institutes and a university. Results will be disseminated via conventional publications and at a workshop in March 2012.

In late 2009, a European Food Safety Authority (EFSA)-funded project (Prima phacie) began work to review and test methodologies for conducting pest risk assessment by means of case studies on three phytoplasmas (Candidatus Phytoplasma mali, Ca. P. prunorum, Ca. P. pyri); two bacteria (Acidovorax avenae subsp. citrulli, Xanthomonas citri [=X. axonopodis] pv. citri); two fungi (Guignardia citricarpa, Mycosphaerella dearnessii); two nematodes (Meloidogyne chitwoodi, M. fallax); and an insect (Anoplophora glabripennis). Multiple risk assessment schemes and methods will be applied to each of the case study pests, allowing for a comparative assessment of methods. Methods to assess the effectiveness of possible risk management options for each pest will also be evaluated. The project will further develop the scientific basis for pest risk assessment within the European Community and identify methodologies most suitable for conducting risk assessments and for evaluating the effectiveness of possible risk management options by the EFSA Panel on Plant Health in order to support European decision making. The project lasts 29 months, and is being conducted by an international consortium of 11 partners consisting of phytosanitary organizations, research institutes and a university. Results will be disseminated via conventional publications and at a workshop in March 2012.

Pesticide Risk Indicators (PRIs) are widely used to evaluate and compare the potential health and environmental risks of pesticide use and to guide pest control policies and practices. They are applied to agricultural, landscape and structural pest management by governmental agencies, private institutions and individuals. PRIs typically assess only the potential risks associated with the active ingredients because, with few exceptions, pesticide manufacturers disclose only the identity of the active ingredients which generally comprise only a minor portion of pesticide products. We show that when inert ingredients are identified and assessed by the same process as the active ingredient, the product specific risk can be much greater than that calculated for the active ingredient alone. To maintain transparency in risk assessment, all those who develop and apply PRIs or make decisions based on their output, should clearly disclose and discuss the limitations of the method.

1. Predicting which species are more likely to invade a region presents significant difficulties to researchers and government agencies. Methods for estimating the risk of establishment are often qualitative and rely on consultation with experts and stakeholders. The inherent subjectivity of this process can lead to ambiguities in any estimate of a species' risk of establishment. 2. Using global presence/absence data of insect crop pests employed a self-organizing map (SOM) to categorize regions based on similarities in species assemblages. This technique enabled them to generate a list of species and rank them based on an index of the risk of establishment. However, the sensitivity of this risk list to errors in the presence/absence data has never been tested. 3. We evaluated the sensitivity of the SOM method by altering the original presence/absence data by increasing amounts and compared estimates of risk with those generated by a national coordinating body (Plant Health Australia) utilizing expert stakeholder opinion. 4. The risk list was unaffected by alterations of up to 20% of data over all regions. The error rate we detected in the data was within these limits. 5. Comparison with the expert stakeholder methodology revealed significant differences in the estimates of establishment risk. Further analysis of the Australian data revealed that a number of regions with strong trade links to Australia supported species assemblages similar to those in Australia, suggesting they are possible sources of pest species with high probability of establishment. 6.Synthesis and applications. This analysis confirms that the SOM methodology is a robust tool in the quantification of risk of establishment. In addition, SOMs can deliver a level of objectivity, which can complement current consultative processes employed by many biosecurity agencies around the world, providing a better overall assessment of invasion risk. This assessment can inform research and development funding decisions and incursion management plans for both government and host industries. While SOMs are utilized in this work for the prioritization of pest insects they can potentially be applied to any taxa (pest or native) or at any scale in which the data are available.

A study on the feasibility and the choice of criteria for developing a general outline for a case-specific monitoring regime for transgenic potato has been performed. Possible impacts of genetic modifications on non-target organisms are assessed, considering the direct or indirect effects of metabolic alterations of the GM plants. Criteria for an appropriate risk assessment and recommendations for case-specific monitoring are suggested based on a review of the scientific literature on crop-organism interactions. First, we identify relevant pathways of plant-organism interactions through nutrients, toxins, or mechanisms of attraction and defence. Second, we consider the need for case-specific monitoring, taking into account variability of existing potato varieties and environmental conditions.

Different international plant protection organisations advocate different schemes for conducting pest risk assessments. Most of these schemes use structured questionnaire in which experts are asked to score several items using an ordinal scale. The scores are then combined using a range of procedures, such as simple arithmetic mean, weighted averages, multiplication of scores, and cumulative sums. The most useful schemes will correctly identify harmful pests and identify ones that are not. As the quality of a pest risk assessment can depend on the characteristics of the scoring system used by the risk assessors (i.e., on the number of points of the scale and on the method used for combining the component scores), it is important to assess and compare the performance of different scoring systems. In this article, we proposed a new method for assessing scoring systems. Its principle is to simulate virtual data using a stochastic model and, then, to estimate sensitivity and specificity values from these data for different scoring systems. The interest of our approach was illustrated in a case study where several scoring systems were compared. Data for this analysis were generated using a probabilistic model describing the pest introduction process. The generated data were then used to simulate the outcome of scoring systems and to assess the accuracy of the decisions about positive and negative introduction. The results showed that ordinal scales with at most 5 or 6 points were sufficient and that the multiplication-based scoring systems performed better than their sum-based counterparts. The proposed method could be used in the future to assess a great diversity of scoring systems.

International, regional and national standards for plant health pest risk assessment and examples of their use from countries around the globe were examined together with similar documents from related fields such as animal health, nature conservation and genetically modified organism (GMO) assessment to determine how the consistency of assessing risk, or components of risk, within and between assessments is addressed. A range of approaches was identified that could be adopted and adapted for use in a revised decision support scheme for quarantine pests by the European and Mediterranean Plant Protection Organization (EPPO) to aid consistency. No single scheme contained a mechanism to ensure or guarantee consistency and no single scheme contained all of the approaches identified to maximize consistency. If the approach of using a five division scale to describe individual components that contribute to evaluating the overall pest risk is to be maintained in the EPPO scheme, then the primary needs required in the EPPO scheme to enhance consistency are (i) the provision of examples that describe divisions within the scales, or alternative but equivalent descriptors that allow assessors to distinguish between divisions, and (ii) a mechanism to combine risk elements in a consistent and transparent way. Features that would help inexperienced assessors include a clear structure, clear rating guidance, questions posed unambiguously, provision of standardized answers and an easily applicable method to interpret and summarize risk ratings. Beyond improvements to the EPPO scheme, assessors using the scheme will need training. Providing links to information and suggesting data sources that would help assessors answer questions would also be helpful (this is being addressed in Work Package 1 of PRATIQUE).

Light brown apple moth (LBAM), Epiphyas postvittana, is a leafroller pest native to Australia and currently has limited distribution around the world. The moth is an extremely polyphagous species which can feed on more than 250 host plants, including many important economic crops such as fruit, vegetable and ornamental species. Epiphas postvittana is also well-known for its polymorphism with respect to its morphology. Its physiology and biology have been well studied compared with many other pest species. For the past 10 years, however, this moth has been gradually expanding its territory around the world. This has resulted in increasing calls for targeted risk assessment so that appropriate quarantine measurements can be put in place to prevent its entry and spread into new regions. Three important aspects related to risk of establishment by E. postvittana were investigated in this study, 1) E. postvittana potential global distribution based on climate, 2) the genetic variation of a target gene for its potential to assess population fitness and invasibility, and 3) the potential use of barcoding as molecular tool for E. postvittana identification at the border. By comparing the climatic conditions of its native (Australia) and long-established (New Zealand) ranges to the rest of the world using CLIMEX, it is suggested that E. postvittana has potential to establish in countries in Central and South America, southern Africa, west Europe and South-east Asia. However, the predicted global distribution of E. postvittana using a range of other types of species distribution models suggested that there are additional climatically suitable areas around the world where this species could potentially survive and establish. Morphological identification of E. postvittana has been problematic which increased the risk of it esacaping detection at the border of countries that wish to regulate this pest. In this study, we sequenced the COI gene from 26 samples of E. postvittana from four populations in New Zealand. We found that the intraspecies variation of E. postvittana is less than 3%, while interspecies variation between E. postvittana and other tortricid species available in the barcode of life database (BOLD) system is much greater than 3%. This result confirms that using barcodes for identification of E. postvittana for biosecurity purposes is practical. The COI gene sequences have been submitted to GenBank as reference sequences. Genetic analysis of the phosphoglucose-isomerase (Pgi) gene in E. postvittana was investigated based on its association with various characteristics of fitness in other Lepidoptera. Using novel PCR primers developed in this study, a comparison of 957 bp of the Pgi coding region amongst four E. postvittana populations revealed 70 segregating sites including 61 synonymous and nine non-synonymous sites. Introns of Pgi gene also show a great variation in length among populations and between alleles within the same locus. The significant variation of Pgi gene in E. postvittana populations indicates the Pgi gene as a useful target gene to assess fitness factors associated with invasibility of E. postvittana. Modeling species distributions and pest identification are both key components in pest risk assessment. The study of fitness-associated genetic variation is currently a novel approach additional approach to risk assessment of invasive species but has much potential in this area. Our study provides basic but important information for further assessment of the establishment capacity of this species in new habitats. Further research in these areas will provide the knowledge required to make science-based decisions in biosecurity.

The last few decades have been turbulent for the reputation and practice of arthropod classical biological control. Public and scientific support for this pest management approach has risen, fallen and appears to be rising again. Due to reports in the 1980s and 1990s of negative environmental effects caused by classical biological control agents, practitioners have scrambled to develop better risk assessment measures. Since the mid-1990s, several national and international guidelines have been created that assign responsibilities to the players involved in selection and release of exotic beneficial insects. At the same time and on a more technical level, researchers have been working to develop standardised procedures for the risk assessment of proposed classical biological control agents. The lack of well-established protocols (like those that exist for weed biological control) has been a great impediment to the implementation of meaningful risk assessments. Along with other research groups, the biological control scientists at CABI Europe-Switzerland are using current projects to tackle problems associated with estimating agent host speci­ficity and risk assessment. In particular, the arthropod classical biological control team is working on key host range testing issues including methods for selection of non-target species, design and implementation of host specificity experiments, and extrapolation of laboratory results to a field context.